noun. a small, swelling red bump on your eyelid
Your eyelid has tiny glands that produce an oily substance to help keep your eyes moist. When one of those glands gets blocked, you can wind up with a chalazion, a swollen, pain-free gland.
Chalazia may develop when something blocks a small oil gland in the eyelid. These glands help keep the eye moist. A blocked gland begins retaining oil and swells. Eventually, the fluid will drain, and you may have a hard lump on your eyelid.
Some additional causes of chalazia are:
Rosacea (a skin condition that causes redness and acne)
Chronic blepharitis, eyelid inflammation (redness, swelling and irritation)
Seborrheic dermatitis (red, dry, flaky and itchy skin)